I came here today to see if anyone had asked for this feature. If not, I was going to start a thread on it.
Upvoted.
While I thank people who gave workaround ideas, they are not as good as having sections within a note you can jump to through links. Separate notes, even with a TOC, are much more unwieldy, especially when it's a document you are constantly adding to. With separate notes, you then have to add each new note to the TOC and then add a back link to the TOC from the new note, so that you can quickly hop between the various "sections". I do this constantly, because it's currently the only way to achieve something close to what I want, but I would much rather have links to take me to different sections within a note.
I've seen similar things on webpages. I think there must be a way to implement this in Evernote.